painting basement floor

Hello. I'm going to be painting my basement floor and looking for some prep suggestions. I'm probably going w an epoxy bc that will stand up better from what I understand. The floor has previously been painted. The paint seems to have held up pretty well in most of the basement. Should I scrape any loose spots use a good degreaser and then paint. Should I use muriatic acid?(read that should only be used on unpainted concrete. Any suggestions appreciated.

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You need to find out what product is on the floor now. Epoxy is a 'hot' material and can lift previous coatings, even ones in good condition.

If you don't want to strip the floor, your best bet is to clean it well and apply the same material again or something in the same material family that will be compatible. (Water base on water base, solvent on solvent)

Epoxies are tough coatings but they are tricky to get applied right, and generally require a lot of prep.

If you are going to use epoxy, it should be applied on bare concrete. The only exception would be if the prior coating was epoxy. Due to the tenacious chemical adhesion of epoxy, it may shear a paint underneath it, which would delaminate the whole coating system. Epoxy also is part A/B, there is an induction period, and it must be applied within a specific time period (referred to as "pot life").

Unfortunately I have no idea what's on the floor. All I know is that the paint looked fairly clean and new 4 years ago. The majority of the paint has held up well aside from a few small areas where I had some water intrusion. I just installed a perimeter drain system and I figure since my knees are already hurting I may as well do the floor too.

Hello. I'm going to be painting my basement floor and looking for some prep suggestions. I'm probably going w an epoxy bc that will stand up better from what I understand. The floor has previously been painted. The paint seems to have held up pretty well in most of the basement. Should I scrape any loose spots use a good degreaser and then paint. Should I use muriatic acid?(read that should only be used on unpainted concrete. Any suggestions appreciated.

Epoxy will stand up better than a conventional coating, but what kind of traffic are you gonna be exposing this floor to? If you're just talking about foot traffic, a high quality acrylic satin finish will also "stand up" just fine - at a lesser cost.

If you still choose to use an epoxy, go to an independent paint dealer and ask for his/her recommendation regarding surface prep and ask for his/her recommendation regarding this preparation and application - Epoxies can be tricky if you're not familiar with them.

As far as surface prep goes - it really won't matter what is on the floor right now (few people will agree with me on that, but I'll get to that in a minute). The surface must be clean (free of dust, dirt, grease, etc.)…it must be free of loose and peeling paint…testing should be done on the areas that "appear" to be in good condition by performing a cross-hatch adhesion test - it'd help to determine the cause of those areas that aren't in good condition. If the existing coating is glossy, it should be sanded with a medium grade paper (not to remove coating, but to create a necessary profile for maximum adhesion for new coating). Do not use muriatic acid…If all these preps are conducted, and assuming the remaining coating passes the adhesion test, you're pretty much good to go with any type of coating you decide on, with only a couple of caveats.

Epoxy is available in many different presentations (solvent borne epoxy, waterborne epoxy, polyamide cure, polyamine cure, epoxy esther, acrylic modified, etc. etc.) - and, of course, each has it's own advantages & disadvantages…If you're looking for a true epoxy that has the ability to withstand just about anything you're gonna throw at it, stay with a 2 component epoxy (must mix parts A & B). Personally, I'd go with a Water-borne 2 component polyamine or polyamide cure product - I would not go with a 2 component acrylic epoxy.

As long as you stay with a water-borne, there will be no incompatibility with whatever is on the floor and the epoxy - there are no hot solvents in water-bornes (WB) as there are in the epoxies that JMays spoke of…I'm not going to go into the differences between poly amines and polyamides on this post, but generally, very generally - poly amines are a 4/1 mixture (short filled gallon of epoxy mixed with 1 quart of activator or catalyst - polyamides are usually a 1/1 mix (1 part epoxy mixed with 1 part catalyst). Both will perform very well for your application.

Epoxy summary - Do not use a solvent borne epoxy - Use WB. Do not use an acrylic epoxy (there is really nothing wrong with acrylic epoxies, the reward generally doesn't justify the cost difference over conventional single component floor paints). Epoxy esthers are single component "epoxies" and are available in both an acrylic and alkyd modified.

There is also mixing and application instructions different than that of conventional coatings. Follow all manufacturers recommendations explicitly. If you then choose to go with a more conventional coating - I'd go with an acrylic floor enamel (some are straight acrylic, some are epoxy esther, some may be modified with urethane). There are many exceptional acrylic floor enamels on the market - they are easy to apply, dry quickly, performs very well in typical, normal household exposure, available in lower sheens (satin, semi as opposed to high gloss finishes in most epoxies)…and are especially easy to recoat and maintain. Personally, I'd also stay away from oil-based (alkyd) floor coatings - they are fine coatings, but they are more expensive, may require more surface prep, harder to recoat and maintain).

Sorry to be so long-winded, but when choosing the right product for painting any floor, you need to be aware of the advantages and limitations of all coatings being considered. Good luck and let us know what you decide.

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I appreciate your in depth response. This room will for the most part will just be foot traffic. So if I clean really well with maybe some tsp or simple green then a light sanding I should be just good with an acrylic latex paint?

I appreciate your in depth response. This room will for the most part will just be foot traffic. So if I clean really well with maybe some tsp or simple green then a light sanding I should be just good with an acrylic latex paint?

Yup…you'd be good. Except I wouldn't use TSP…I'm not real familiar with Simple Green, I'd use Soilax or Dirtex Powder. If you choose to use TSP, make sure you rinse completely and allow to dry before painting. Good Luck.

Ok don't know where to find those products locally but I'll keep looking. Doesn't look like the big box stores sell them. Reason I was thinking tsp is bc it acts as a deglosser and may alleviate the need to sand. Paint Doesn't appear too glossy anyhow.

Ok don't know where to find those products locally but I'll keep looking. Doesn't look like the big box stores sell them. Reason I was thinking tsp is bc it acts as a deglosser and may alleviate the need to sand. Paint Doesn't appear too glossy anyhow.

You're thinking isn't wrong - TSP can be an effective de-glosser and is a fine detergent cleaner - Independent paint dealers (as opposed to big boxes) would be more familiar with the advantages of products like Soilax or Dirtex Powder over TSP…

The "problems" with TSP, as it relates to your specific situation, are (1) without complete and proper rinsing to neutralize a surface cleaned with TSP, a film containing phosphates are left on the surface - In other forms, phosphates are a fertilizer that plant life thrives on…Mildew & Algae are examples of such plant life and a surface treated with TSP could provide the necessary food source for these spores to flourish….and (2) While TSP is strong enough to serve as a deglosser of paint, it won't necessarily create the "profile" for a good mechanical bond. Think of a teflon skillet - when frying on a new teflon skillet nothing sticks to it - no matter how many times you clean with detergent…but just once take a metallic scrub pad to it and see how difficult it is to flip a fried egg - the "scoring" or profiling of a surface creates a much tighter adhesion.

It sounds like you've got a pretty good handle on how to prep and paint this surface - your ideas are not wrong - there is just other ways to kind of accomplish the same result with less work AND less possibility of something going wrong.